LT8494

1

8494fa

For more information www.linear.com/LT8494

INPUT VOLTAGE (V)

0

12

24

36

48

60

0

5

10

15

20

8494 TA01b

TYPICAL APPLICATION

FEATURES

DESCRIPTION

SEPIC/Boost DC/DC

Converter with 2A, 70V Switch,

and 7µA Quiescent Current

The LT®8494 is an adjustable frequency (250kHz to

1.5MHz) monolithic switching regulator. Quiescent cur-

rent can be less than 7µA when operating and is ~0.3µA

when SWEN is low. The LT8494 can be configured as

either a SEPIC, boost or flyback converter.

The low ripple Burst Mode operation maintains high

efficiency at low output current while keeping output rip-

the part to automatically operate from the most efficient

supply. Input supply voltage can be up to 60V for SEPIC

topologies and up to 32V (with ride-through up to 60V)

for boost and flyback topologies. After start-up, battery

life is extended since the part can draw current from its

Using a resistor divider on the SWEN pin provides a pro-

grammable undervoltage lockout (UVLO) for the con-

of the programmed output voltage.

Additional features such as frequency foldback and soft-

start are integrated. The LT8494 is available in 20-lead

QFN and 20-lead TSSOP packages with exposed pads

for low thermal resistance. Fault tolerance in the TSSOP

allows for adjacent pin shorts or an open without raising

the output voltage above its programmed value.

450kHz, 5V Output SEPIC Converter

No-Load Supply Current

Efficiency

APPLICATIONS

n

n

n

Output Ripple (<10mV Typ.)

n

Dual Supply Pins:

n

Improves Efficiency

n

Reduces Minimum Supply Voltage to ~1V After

n

Start-Up to Extend Battery Life

n

Wide Input Voltage Range of ~1V to 60V (2.5V to

32V for Start-Up)

n

PG Functional for Input Supply Down to 1.3V

n

FMEA Fault Tolerant in TSSOP Package

n

Fixed Frequency PWM, SEPIC/BOOST/FLYBACK

Topologies

n

NPN Power Switch: 2A/70V

n

Programmable Switching Frequency: 250kHz to 1.5MHz

n

UVLO Programmable on SWEN Pin

n

Soft-Start Programmable with One Capacitor

n

Small 20-Lead QFN or 20-Lead TSSOP Packages

n

Automotive ECU Power

n

Power for Portable Products

n

Industrial Supplies

L

, LT, LTC, LTM, Linear Technology, Burst Mode and the Linear logo are registered trademarks of

Analog Devices, Inc. All other trademarks are the property of their respective owners.

2.2µF

15µH

1µF

3V TO 60V

5V

SW

BIAS

FB

GND

SWEN

RT

PG

SS

1M

316k

8494 TA01a

169k

LT8494

47µF

×2

4.7pF

4.7µF

LOAD CURRENT (A)

0.0

0.2

0.4

0.6

0.8

1.0

60

65

70

75

80

85

90

8494 TA01c